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We investigate charge and spin currents that may appear in some materials, considering the possible couplings and the symmetries of a field-theoretical model presented here. We inspect these possible currents in (1+2) dimensions by adopting an N =2 - D=3 supersymmetric framework with a Chern-Simons term and non-minimal couplings as well. We discuss a number of aspects in connection with a vortex configuration that is topologically viable. The new features of our investigation take into account the nature of both the U(1)-symmetry and supersymmetry (SUSY) breakings in presence of the vortex. We focus on aspects of the fermionic sector and their interactions with the currents. In connection with the spectrum of fermions, we also derive the mass gap in terms of the parameters of the the model. Another point we highlight is the role SUSY in our considerations. Once graphene and topological insulator materials are described by a Dirac-like equation, we assume, as a working hypothesis, that SUSY may also have some influence on the properties of these materials. Along this line, it is mandatory to connect the SUSY breakdown to this class of materials. We believe that our discussion could bring some elements for the understanding of this category of lower-dimensional systems., Comment: 20 pages and 5 figures

We pursue, in this contribution, an investigation of the contribution of the electron's magnetic dipole moment (MDM) to the electron's electric dipole moment (EDM) (or the charged leptons, more generally) in the framework of the Born-Infeld Electrodynamics and in a gravity background with a non-vanishing cosmological constant, where CP-symmetry is broken down. Our point of view consist in associating a non-trivial EDM to a non-symmetry of the charge distribution of the elementary particle under consideration. The bound on the electron's EDM published in 2014 is used to constrain the coupling parameter of the electromagnetic sector to the scalar curvature of the space-time in the case we consider gravity to be responsible for the asymmetry in the distribution.

The mechanism of dynamical mass generation for the gauge field is studied through 1-loop. We find out that torsion is an obstruction to the appearance of a 1-loop mass correction. Contrary, if torsion is not present, a mass gap is generated for the 2-form field., Comment: 9 pages, 2 figures

Tumor Associated Glycoprotein 72 (TAG-72) is common to most epithelial tumors. In this study serum levels of TAG-72 were measured in 36 healthy female subjects, in 94 patients with breast cancer, and in 43 others with epithelial ovarian cancer. More particularly, 27 out of the 94 patients with breast cancer had early disease (Stage I-I; or T 0-2b; N 0-1b; M 0), while the remaining 67 had advanced disease (Stage III-IV; or T 0-4; N 0-3; M 0-1). All the 43 subjects with ovarian cancer were at stage III-IV (FIGO Classification), 12 of whom had minimal disease (lesions less than 2 cm) and the other 31 had bulky disease. 3.5 U/ml being the highest value found in the control group, we arbitrarily assumed 3.85 U/ml (mean +/- 3 SD) as the cut-off limit in this preliminary study. Among the patients with breast cancer, 17 out of the 67 subjects with advanced disease (25.3%) and 1 out of the 27 others with early disease (3.7%) exceeded the TAG-72 cut-off limit. Among the patients with ovarian cancer, 2 out of the 12 subjects with minimal disease (16.7%) and 22 out of the others 31 with bulky disease (70.9%) had TAG-72 levels above cut-off limit. High TAG-72 levels were found in all the histotypes of ovarian cancer including the mucinous type. Preliminary data seem to indicate that in ovarian cancer variations in serum levels of TAG-72 are in agreement with the trend of the disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum thyroglobulin in patients with early thyroid cancer who have residual thyroid after total thyroidectomy

Although subclinical hypothyroidism is frequently diagnosed, the decision to institute a substitutive therapy with L-T4 remains controversial. Because the cardiovascular system is considered a main target for the action of thyroid hormone, we investigated whether subclinical hypothyroidism induces cardiovascular abnormalities. Twenty-six patients (mean age, 36 +/- 12 yr) were evaluated by Doppler-echocardiography, whereas a subgroup of 10 patients, randomly selected, were reevaluated after 6 months of L-T4 substitutive therapy (mean dose, 68 microg daily). Thirty subjects (matched for age, sex, and body surface area) served as controls. Mean plasma TSH was significantly higher in patients (P < 0.001), whereas mean serum free T4 and free T3 concentrations, although in the normal range, were significantly lower (P < 0.001 and P < 0.005, respectively). Blood pressure and heart rate did not differ from control values. Echocardiogram examination showed no abnormalities of the left ventricular morphology and a slight, but not significant, reduction in the systolic function in the patient group. In contrast, Doppler-derived indices of diastolic function showed significant prolongation of the isovolumic relaxation time (94 +/- 13 vs. 84 +/- 8 msec; P < 0.001), increased A wave (55 +/- 13 vs. 48 +/- 9 cm/sec; P < 0.05), and reduced early diastolic mitral flow velocity/late diastolic mitral flow velocity ratio (1.4 +/- 0.3 vs. 1.7 +/- 0.3; P < 0.001). In the subgroup of 10 patients, thyroid hormone profile was normalized by 6 months of L-T4 substitutive therapy, whereas no changes were observed in the left ventricular morphology. Systolic function was significantly enhanced, as compared with pretreatment values (P < 0.01) but did not differ from control values. Also, systemic vascular resistance was significantly decreased by L-T4 replacement therapy. Assessment of diastolic function showed significant shortening of isovolumic relaxation time (77 +/- 15 vs. 91 +/- 8; P < 0.05), reduction of A wave (51 +/- 13 vs. 60 +/- 12; P < 0.01), and increase of early diastolic mitral flow velocity/late diastolic mitral flow velocity ratio (1.7 +/- 0.4 vs. 1.3 +/- 0.3; P < 0.001). These indices, however, were comparable with those of control subjects. These findings indicate that subclinical hypothyroidism affects diastolic function and that this abnormality may be reversed by L-T4 substitutive therapy.

The authors have analysed the theoretical and clinical implications of a biological approach to radioimmu-noscintigraphy (RIS), a new diagnostic technique based on the in vivo reaction between radiolabelled monoclonal antibodies and tumor-associated antigens expressed by the neoplastic cells. The assumption is that, as in all radioisotopic procedures, the radioimmunoscintigraphic image is the expression of differences in concentration (and not in density) between adjacent tissues. This “biological premise” is analysed to demonstrate a possible role of RIS not only in diagnosis but also in prognosis and therapy. A comparison with other imaging procedures and with histopathology, considered as the “gold stand-ard” of the present-day morphological approach to diagnosis, is also discussed. Finally, biological premises, as well as the initial results and prospects regarding the use of high doses of radiolabelled monoclonal antibodies for therapeutic purposes are presented.

OBJECTIVE: This phase III study was aimed at evaluating whether the addition of gemcitabine (G) to vinorelbine (V) could improve the survival and quality of life (QoL) of elderly patients with advanced NSCLC. PATIENTS AND METHODS: Patients with advanced NSCLC, aged >or=70 years, were randomly allocated to receive V 30 mg/m(2) on days 1 and 8 every 3 weeks or G 1200 mg/m(2) plus V 30 mg/m(2) on days 1 and 8 every 3 weeks. Survival was the main end point of the study. The estimated sample size was 120 patients per arm, but an interim analysis of survival was planned on the first 60 patients per arm. RESULTS: In May 1999, an interim analysis was performed with the survival data of the first 120 eligible patients (V(arm)=60, G+V(arm)=60). Forty-nine patients had stage IIIB disease and 71 patients stage IV disease, median potential follow-up of 14 months (range; 3-22), 93 patients had died (G+V(arm)=41, V(arm)=52). Median survival time (MST) was 29 weeks and projected 1-year survival was 30% in the G+V(arm); these values were 18 weeks and 13% in the V(arm). At multivariate Cox analysis, the risk of death in the G+V(arm) compared with V(arm) was 0.48 (95% C1=0.29-0.79; P

In a 28-year-old man with Cushing's syndrome, studies investigating a hypophyseal and/or adrenal origin of the disease, including computed tomography and magnetic resonance imaging, were negative. In agreement with reports showing somatostatin receptors on the cell membrane of ectopically secreting ACTH tumours, scintigraphy was performed after intravenous injection of 111 MBq 111In-pentetreotide (OCT). The radiolabelled OCT scan showed a small focal area of intense uptake at the inferior lobe of the right lung. Subsequent radioguided surgery located and defined a small mass (1.8 x 1.4 x 1.6 cm). The probe pinpointed the mass to the right inferior chest lobe, with a tumour/normal tissue count ratio of 6:1 and tumour/hilar normal lymph node ratio of 12:1, thus permitting the complete excision of the tumour to exclude lymph node and/or parietal involvement. A lung carcinoid was diagnosed at histology. The patient is still alive and disease-free 24 months after surgery. 111In-OCT was found to be useful for localizing the ACTH-secreting tumour and also permitted rapid non-invasive differential diagnosis between an ACTH-secreting pituitary adenoma and malignancy causing ectopic ACTH syndrome. This study also showed the clinical usefulness of radioguided surgery in the treatment of bronchial carcinoid.

Two cases of Langerhans cell histiocytosis (LCH) expressing as Hand-Schuller-Christian syndrome with diabetes insipidus, hyperprolactinemia and empty sella are here reported. Up-to-date this four-fold association is lacking in world literature and it is here discussed in the light if LCH is a cancer or the clinical expression of an immunologic disorder.

Lithium carbonate, widely used in the treatment of bipolar patients, is well known to induce thyroid alterations. In this longitudinal study the thyroid function was investigated during lithium treatment over a period of 12 months in 12 euthymic bipolar patients with a normal thyroid function and absence of thyroid antibodies. Nine of the 12 patients were further studied on the 15th month, 5 of these 9 on the 18th month and 4 of the last-mentioned 5 on the 24th month. The mean basal and TRH-stimulated TSH values during lithium therapy were significantly higher as compared to those at the beginning of the treatment. More particularly, during lithium therapy, a significant increase of basal TSH over the normal range was found in 10 out of the 12 patients. A rise of TRH-stimulated TSH was found in 11 out of the 12 patients. The impairment of the hypothalamic-pituitary-thyroid (HPT) axis was transitory in the majority of cases. Two patients developed a nodular goiter during the treatment. Plasma T3, T4, FT3 and FT4 levels did not change during the treatment. Thyroid antibodies remained undetectable. The conclusions of the study are twofold: 1) Subclinical hypothyroidism during lithium therapy is much more frequent than previous cross-sectional studies suggest; 2) Thyroxine replacement in lithium-treated patients is advisable in order to prevent subclinical hypothyroidism and the risk of a subsequent goiter.

Fifteen patients with medullary carcinoma of the thyroid (MCT), who had persistently elevated levels of serum calcitonin (CT) and carcinoembryonic antigen (CEA) after total thyroidectomy, were studied in order to localize the sites of the recurrent disease. Routine diagnostic examinations, including ultrasonography (US) and computed axial tomography (CAT), were carried out in all the cases. Scintigraphy with radio-iodinated meta-iodobenzylguanidine ((131I)-MIBG) was performed in 13 cases; selective venous catheterization (SVC) to reveal a gradient of CT levels was performed in 12 cases. Ten patients underwent both (l31I)-MIBG scintigraphy and SVC. US and CAT revealed the sites of recurrent tumor in only 4 out of the total 15 patients. SVC in basal conditions showed the presence of small metastases in 2 cases, and after intravenous stimulus with pentagastrin in 4 others. The MIBG scan showed metastatic foci of sporadic MCT in 2 patients, residual medullary thyroid tissue in 4 others, and a pheochromocytoma in a previously undiagnosed patient with Sipple’s syndrome. More particularly, MIBG scan and SVC showed the localization of residual or metastatic tumor in 10 cases. In all 10 cases, results of the MIBG scan and SVC were confirmed as true positive by subsequent surgery and histopathologic examination. The conclusions of this study were twofold: (1) in the follow-up of MCT patients with persistently elevated CT and CEA levels, positive US and CAT findings make the MIBG scan useful, if positive, only to determine the nature of the lesion; (2) the association of the two approaches (MIBG scan and SVC) in patients with increased levels of CT and CEA but negative results of routine diagnostic examination can be useful to detect occult rnicrometastases, thus permitting an accurate clinicopathologic staging of the disease.

Twenty patients with known ovarian cancer have been investigated in this pilot study to verify the clinical usefulness of radioimaging using the B72.3 monoclonal antibody labelled with iodine-131. No adverse reactions occurred after intravenous injection of B72.3 MoAb. The radioimaging results were compared with those obtained with other diagnostic methods, including computed X-ray tomography and ultrasound. A sensitivity of 85% in the detection of primary ovarian cancers and collections of ascites, and of 84% in the detection of abdominal and extraperitoneal metastases has been demonstrated using this radioiodinated antibody in vivo. No false localization occurred. Immunohistochemical studies showed no cross-reactions between B72.3 MoAb and mesothelial cells, confirming the high specificity of binding between B72.3 MoAb and neoplastic cells in ascites. Negligible uptake of radiolabelled B72.3 MoAb has been demonstrated in the unaffected ovary. The major advantage of using this monoclonal antibody is related to the expression of a recognized antigen (called TAG 72) in mucinous, serous and in differentiated adenocarcinomas of the ovary.

Transglutaminase (TGase) activity was reduced in intact mitogen-stimulated human peripheral blood lymphocytes (PBL) when compared to intact resting PBL. Moreover, a treatment of the same quiescent immunocompetent cells with purified liver TGase and Ca2+ completely suppressed the mitogen-induced blast transformation. A decrease in TGase activity in neoplastically transformed seminal vesicle epithelial cells with respect to their normal parent counterpart was also observed. Our data support the notion of a possible implication of TGase in cell proliferation and transformation.